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-rw-r--r--drivers/md/dm-emc.c345
1 files changed, 0 insertions, 345 deletions
diff --git a/drivers/md/dm-emc.c b/drivers/md/dm-emc.c
deleted file mode 100644
index 3ea5ad4b7805..000000000000
--- a/drivers/md/dm-emc.c
+++ /dev/null
@@ -1,345 +0,0 @@
1/*
2 * Copyright (C) 2004 SUSE LINUX Products GmbH. All rights reserved.
3 * Copyright (C) 2004 Red Hat, Inc. All rights reserved.
4 *
5 * This file is released under the GPL.
6 *
7 * Multipath support for EMC CLARiiON AX/CX-series hardware.
8 */
9
10#include "dm.h"
11#include "dm-hw-handler.h"
12#include <scsi/scsi.h>
13#include <scsi/scsi_cmnd.h>
14
15#define DM_MSG_PREFIX "multipath emc"
16
17struct emc_handler {
18 spinlock_t lock;
19
20 /* Whether we should send the short trespass command (FC-series)
21 * or the long version (default for AX/CX CLARiiON arrays). */
22 unsigned short_trespass;
23 /* Whether or not to honor SCSI reservations when initiating a
24 * switch-over. Default: Don't. */
25 unsigned hr;
26
27 unsigned char sense[SCSI_SENSE_BUFFERSIZE];
28};
29
30#define TRESPASS_PAGE 0x22
31#define EMC_FAILOVER_TIMEOUT (60 * HZ)
32
33/* Code borrowed from dm-lsi-rdac by Mike Christie */
34
35static inline void free_bio(struct bio *bio)
36{
37 __free_page(bio->bi_io_vec[0].bv_page);
38 bio_put(bio);
39}
40
41static void emc_endio(struct bio *bio, int error)
42{
43 struct dm_path *path = bio->bi_private;
44
45 /* We also need to look at the sense keys here whether or not to
46 * switch to the next PG etc.
47 *
48 * For now simple logic: either it works or it doesn't.
49 */
50 if (error)
51 dm_pg_init_complete(path, MP_FAIL_PATH);
52 else
53 dm_pg_init_complete(path, 0);
54
55 /* request is freed in block layer */
56 free_bio(bio);
57}
58
59static struct bio *get_failover_bio(struct dm_path *path, unsigned data_size)
60{
61 struct bio *bio;
62 struct page *page;
63
64 bio = bio_alloc(GFP_ATOMIC, 1);
65 if (!bio) {
66 DMERR("get_failover_bio: bio_alloc() failed.");
67 return NULL;
68 }
69
70 bio->bi_rw |= (1 << BIO_RW);
71 bio->bi_bdev = path->dev->bdev;
72 bio->bi_sector = 0;
73 bio->bi_private = path;
74 bio->bi_end_io = emc_endio;
75
76 page = alloc_page(GFP_ATOMIC);
77 if (!page) {
78 DMERR("get_failover_bio: alloc_page() failed.");
79 bio_put(bio);
80 return NULL;
81 }
82
83 if (bio_add_page(bio, page, data_size, 0) != data_size) {
84 DMERR("get_failover_bio: bio_add_page() failed.");
85 __free_page(page);
86 bio_put(bio);
87 return NULL;
88 }
89
90 return bio;
91}
92
93static struct request *get_failover_req(struct emc_handler *h,
94 struct bio *bio, struct dm_path *path)
95{
96 struct request *rq;
97 struct block_device *bdev = bio->bi_bdev;
98 struct request_queue *q = bdev_get_queue(bdev);
99
100 /* FIXME: Figure out why it fails with GFP_ATOMIC. */
101 rq = blk_get_request(q, WRITE, __GFP_WAIT);
102 if (!rq) {
103 DMERR("get_failover_req: blk_get_request failed");
104 return NULL;
105 }
106
107 blk_rq_append_bio(q, rq, bio);
108
109 rq->sense = h->sense;
110 memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE);
111 rq->sense_len = 0;
112
113 rq->timeout = EMC_FAILOVER_TIMEOUT;
114 rq->cmd_type = REQ_TYPE_BLOCK_PC;
115 rq->cmd_flags |= REQ_FAILFAST | REQ_NOMERGE;
116
117 return rq;
118}
119
120static struct request *emc_trespass_get(struct emc_handler *h,
121 struct dm_path *path)
122{
123 struct bio *bio;
124 struct request *rq;
125 unsigned char *page22;
126 unsigned char long_trespass_pg[] = {
127 0, 0, 0, 0,
128 TRESPASS_PAGE, /* Page code */
129 0x09, /* Page length - 2 */
130 h->hr ? 0x01 : 0x81, /* Trespass code + Honor reservation bit */
131 0xff, 0xff, /* Trespass target */
132 0, 0, 0, 0, 0, 0 /* Reserved bytes / unknown */
133 };
134 unsigned char short_trespass_pg[] = {
135 0, 0, 0, 0,
136 TRESPASS_PAGE, /* Page code */
137 0x02, /* Page length - 2 */
138 h->hr ? 0x01 : 0x81, /* Trespass code + Honor reservation bit */
139 0xff, /* Trespass target */
140 };
141 unsigned data_size = h->short_trespass ? sizeof(short_trespass_pg) :
142 sizeof(long_trespass_pg);
143
144 /* get bio backing */
145 if (data_size > PAGE_SIZE)
146 /* this should never happen */
147 return NULL;
148
149 bio = get_failover_bio(path, data_size);
150 if (!bio) {
151 DMERR("emc_trespass_get: no bio");
152 return NULL;
153 }
154
155 page22 = (unsigned char *)bio_data(bio);
156 memset(page22, 0, data_size);
157
158 memcpy(page22, h->short_trespass ?
159 short_trespass_pg : long_trespass_pg, data_size);
160
161 /* get request for block layer packet command */
162 rq = get_failover_req(h, bio, path);
163 if (!rq) {
164 DMERR("emc_trespass_get: no rq");
165 free_bio(bio);
166 return NULL;
167 }
168
169 /* Prepare the command. */
170 rq->cmd[0] = MODE_SELECT;
171 rq->cmd[1] = 0x10;
172 rq->cmd[4] = data_size;
173 rq->cmd_len = COMMAND_SIZE(rq->cmd[0]);
174
175 return rq;
176}
177
178static void emc_pg_init(struct hw_handler *hwh, unsigned bypassed,
179 struct dm_path *path)
180{
181 struct request *rq;
182 struct request_queue *q = bdev_get_queue(path->dev->bdev);
183
184 /*
185 * We can either blindly init the pg (then look at the sense),
186 * or we can send some commands to get the state here (then
187 * possibly send the fo cmnd), or we can also have the
188 * initial state passed into us and then get an update here.
189 */
190 if (!q) {
191 DMINFO("emc_pg_init: no queue");
192 goto fail_path;
193 }
194
195 /* FIXME: The request should be pre-allocated. */
196 rq = emc_trespass_get(hwh->context, path);
197 if (!rq) {
198 DMERR("emc_pg_init: no rq");
199 goto fail_path;
200 }
201
202 DMINFO("emc_pg_init: sending switch-over command");
203 elv_add_request(q, rq, ELEVATOR_INSERT_FRONT, 1);
204 return;
205
206fail_path:
207 dm_pg_init_complete(path, MP_FAIL_PATH);
208}
209
210static struct emc_handler *alloc_emc_handler(void)
211{
212 struct emc_handler *h = kzalloc(sizeof(*h), GFP_KERNEL);
213
214 if (h)
215 spin_lock_init(&h->lock);
216
217 return h;
218}
219
220static int emc_create(struct hw_handler *hwh, unsigned argc, char **argv)
221{
222 struct emc_handler *h;
223 unsigned hr, short_trespass;
224
225 if (argc == 0) {
226 /* No arguments: use defaults */
227 hr = 0;
228 short_trespass = 0;
229 } else if (argc != 2) {
230 DMWARN("incorrect number of arguments");
231 return -EINVAL;
232 } else {
233 if ((sscanf(argv[0], "%u", &short_trespass) != 1)
234 || (short_trespass > 1)) {
235 DMWARN("invalid trespass mode selected");
236 return -EINVAL;
237 }
238
239 if ((sscanf(argv[1], "%u", &hr) != 1)
240 || (hr > 1)) {
241 DMWARN("invalid honor reservation flag selected");
242 return -EINVAL;
243 }
244 }
245
246 h = alloc_emc_handler();
247 if (!h)
248 return -ENOMEM;
249
250 hwh->context = h;
251
252 if ((h->short_trespass = short_trespass))
253 DMWARN("short trespass command will be send");
254 else
255 DMWARN("long trespass command will be send");
256
257 if ((h->hr = hr))
258 DMWARN("honor reservation bit will be set");
259 else
260 DMWARN("honor reservation bit will not be set (default)");
261
262 return 0;
263}
264
265static void emc_destroy(struct hw_handler *hwh)
266{
267 struct emc_handler *h = (struct emc_handler *) hwh->context;
268
269 kfree(h);
270 hwh->context = NULL;
271}
272
273static unsigned emc_error(struct hw_handler *hwh, struct bio *bio)
274{
275 /* FIXME: Patch from axboe still missing */
276#if 0
277 int sense;
278
279 if (bio->bi_error & BIO_SENSE) {
280 sense = bio->bi_error & 0xffffff; /* sense key / asc / ascq */
281
282 if (sense == 0x020403) {
283 /* LUN Not Ready - Manual Intervention Required
284 * indicates this is a passive path.
285 *
286 * FIXME: However, if this is seen and EVPD C0
287 * indicates that this is due to a NDU in
288 * progress, we should set FAIL_PATH too.
289 * This indicates we might have to do a SCSI
290 * inquiry in the end_io path. Ugh. */
291 return MP_BYPASS_PG | MP_RETRY_IO;
292 } else if (sense == 0x052501) {
293 /* An array based copy is in progress. Do not
294 * fail the path, do not bypass to another PG,
295 * do not retry. Fail the IO immediately.
296 * (Actually this is the same conclusion as in
297 * the default handler, but lets make sure.) */
298 return 0;
299 } else if (sense == 0x062900) {
300 /* Unit Attention Code. This is the first IO
301 * to the new path, so just retry. */
302 return MP_RETRY_IO;
303 }
304 }
305#endif
306
307 /* Try default handler */
308 return dm_scsi_err_handler(hwh, bio);
309}
310
311static struct hw_handler_type emc_hwh = {
312 .name = "emc",
313 .module = THIS_MODULE,
314 .create = emc_create,
315 .destroy = emc_destroy,
316 .pg_init = emc_pg_init,
317 .error = emc_error,
318};
319
320static int __init dm_emc_init(void)
321{
322 int r = dm_register_hw_handler(&emc_hwh);
323
324 if (r < 0)
325 DMERR("register failed %d", r);
326
327 DMINFO("version 0.0.3 loaded");
328
329 return r;
330}
331
332static void __exit dm_emc_exit(void)
333{
334 int r = dm_unregister_hw_handler(&emc_hwh);
335
336 if (r < 0)
337 DMERR("unregister failed %d", r);
338}
339
340module_init(dm_emc_init);
341module_exit(dm_emc_exit);
342
343MODULE_DESCRIPTION(DM_NAME " EMC CX/AX/FC-family multipath");
344MODULE_AUTHOR("Lars Marowsky-Bree <lmb@suse.de>");
345MODULE_LICENSE("GPL");
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